Modern day data processing systems are often made up of several processor units, several memory storage units, several control units and a variety of input output devices. Often each of these units is housed in one or more cabinets arranged within a specially designed computer room. The use of cabinets is particularly useful where the data processing system is modularized, i.e., its capacity can be increased or decreased by adding or removing cabinets. Such cabinets have found use more and more with the advent of circuit boards, each of which has mounted or otherwise formed thereon complete logic arrays. Several of these circuit boards may be removably disposed in each cabinet and are of such a nature that in the maintenance or trouble shooting of the data processing system they may be removed and replaced with little effort.
The cabinets which house such circuitry generally provide easy access for such replacement. Panels or doors secured to the cabinets by screws or the like which may be removed provide one manner in which such access may be provided.
Another way is simply to provide each cabinet with hinged doors which may be opened to allow maintenance or testing of the various components. Often times it is advantageous to remove the door completely to permit major repair or replacement of one or more defective circuit board or in the actual factory assembly of circuitry and electrical interconnection during the manufacturing process.
In the field where on site maintenance occurs, the various cabinets are generally arrayed in side by side or adjacent relationship. In such an environment, the door hinges must be such as to permit the door to be easily removed without serious interference with adjacent cabinets.